Simplify the code to starting to integrate with the new design of networkcache http server.

src/zc/buildout/networkcache.py

@@ -13,39 +13,36 @@
 ##############################################################################
 
 
+import hashlib
 import os
 import posixpath
-import hashlib
-from libnetworkcache import NetworkcacheClient
+import re
+from download import check_md5sum
+from slapos.tool.libnetworkcache import NetworkcacheClient
 
 
-def _get_hash_from_file(path, hash_object):
-    """
-      Calculate the hash from file.
-    """
-    f = open(path, 'rb')
-    try:
-        chunk = f.read(2**16)
-        while chunk:
-            hash_object.update(chunk)
-            chunk = f.read(2**16)
-        return hash_object.hexdigest()
-    finally:
-        f.close()
+_md5_re = re.compile(r'md5=([a-f0-9]+)')
 
 
-def check_sha256sum(path, sha256sum):
-    """Tell whether the SHA256sum checksum of the file at path matches
-    """
-    return sha256sum == _get_hash_from_file(path, hashlib.sha256())
+def _get_md5_from_url(url):
+  match = _md5_re.search(url)
+  if match:
+    return match.group(1)
+  return None
 
 
-def _update_network_cached_log(key, url):
+def _update_network_cached_log(path, url):
     """Update the networkcached.log file.
 
     Adding the last key and URL which has been retrieved from networkcached server.
 
     """
+    f = open(path, 'r')
+    try:
+      key = hashlib.sha512(f.read()).hexdigest()
+    finally:
+      f.close()
+
     # Keep the log
     map_path = os.path.join(os.environ.get('PWD'), '.networkcached.log')
     mode = 'r+'
@@ -66,7 +63,7 @@ def _update_network_cached_log(key, url):
         f.close()
 
 
-def download_network_cached(network_cache, path, url, logger):
+def download_network_cached(network_cache, path, url, logger, md5sum=None):
     """Download from a network cache provider
 
     If something fail (providor be offline, or hash_string fail), we ignore
@@ -77,19 +74,33 @@ def download_network_cached(network_cache, path, url, logger):
     if network_cache in (None, '',):
         # Not able to use network cache
         return False
+    if md5sum is None:
+        print "URL ", url
+        md5sum = _get_md5_from_url(url) 
+
+    # XXX (lucas): This will be removed.
+    key = hashlib.sha512(url).hexdigest()
 
-    key = hashlib.sha256(url).hexdigest()
     network_cached_url = os.path.join(network_cache, key)
     logger.info('Downloading from network cache %s' % network_cached_url)
     try:
         nc = NetworkcacheClient(network_cache)
-        result, path = nc.get(key, path)
+        result = nc.get(key)
+
         if result.status != 200:
           logger.info('Fail to download from network cache: File Not Found.')
           return False
 
-        if not check_sha256sum(path, result.getheader('x-sha256sum')):
-            logger.info('SHA256 checksum mismatch downloading %r' % \
+        file_content = result.read()
+        # save the file
+        f = open(path, 'w+b')
+        try:
+          f.write(file_content)
+        finally:
+          f.close()
+
+        if not check_md5sum(path, md5sum):
+            logger.info('MD5 checksum mismatch downloading %r' % \
                                                            network_cached_url)
             return False
     except IOError, e:
@@ -107,12 +118,11 @@ def upload_network_cached(network_cache, external_url, path, logger):
          'Upload cache ignored, network-cache was not provided')
         return False
 
-    key = hashlib.sha256(external_url).hexdigest()
     try:
         nc = NetworkcacheClient(network_cache)
-        result = nc.put(key, path)
+        result = nc.put(path)
         if result.status == 200:
-            _update_network_cached_log(key, external_url)
+            _update_network_cached_log(path, external_url)
 
     except (IOError, EOFError), e:
         logger.info('Fail to upload cache on %s. %s' % \